Turbine shroud with sealing features

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to and the benefit of U.S. Provisional Patent Application No. 62/240,233, filed 12 Oct. 2015, the disclosure of which is now expressly incorporated herein by reference.

FIELD OF THE DISCLOSURE

The present disclosure relates generally to gas turbine engines, and more specifically to turbine shrouds used in gas turbine engines.

BACKGROUND

Gas turbine engines are used to power aircraft, watercraft, power generators, and the like. Gas turbine engines typically include a compressor, a combustor, and a turbine. The compressor compresses air drawn into the engine and delivers high pressure air to the combustor. In the combustor, fuel is mixed with the high pressure air and is ignited. Exhaust products of the combustion reaction in the combustor are directed into the turbine where work is extracted to drive the compressor and, sometimes, an output shaft, fan, or propeller.

Compressors and turbines typically include alternating stages of static vane assemblies and rotating wheel assemblies. The rotating wheel assemblies include disks carrying blades around their outer edges. When the rotating wheel assemblies turn, tips of the blades move along blade tracks included in static shrouds that are arranged around the rotating wheel assemblies. Such static shrouds may be coupled to an engine case that surrounds the compressor, the combustor, and the turbine.

Some shrouds are made up of a number of segments arranged circumferentially adjacent to one another to form a ring. Blade tracks of such shrouds inhibit exhaust gas from leaking through the shroud during operation of the gas turbine engine. Thus, more exhaust gas is directed to the blades of the rotating turbine wheel assembly that extracts work from the gas.

SUMMARY

The present disclosure may comprise one or more of the following features and combinations thereof.

According to the present disclosure, a turbine shroud assembly that extends around a central axis is taught. The assembly may include a carrier segment that extends partway around the central axis and that forms a cavity that opens in a radially-inward direction, a first retainer positioned within the cavity of the carrier segment, the first retainer including at least one attachment post extending radially outward to attach the first retainer to the carrier segment and at least one flange extending radially inward from the attachment post, and a first blade track segment comprising ceramic-containing materials, the first blade track segment formed to include a runner that extends partway around the central axis and the at least one hanger that extends radially outward from the runner into the cavity of the carrier segment to engage at least one flange of the first retainer to mount the first blade track segment thereto.

In some embodiments, the assembly may include a compartment seal. The compartment seal may be disposed to encircle the at least one hanger and engage the runner to seal a portion of the cavity disposed radially outward of the runner of the blade track.

In some embodiments, at least one attachment post of the retainer may be arranged to penetrate through an opening in the carrier segment to attach the retainer to the carrier segment.

In some embodiments, the assembly may include a second blade track segment. The second blade track segment may include a runner that extends partway around the central axis, each of the first and the second blade track segments includes two hangers that extend radially outward from the runner. The compartment seal may encircle the hangers of the first and the second blade track segments, and the compartment seal is disposed in contact with a top surface of the runner.

In some embodiments, the assembly may include a second retainer configured to mount onto the second blade track segment. The first and the second retainers are configured to attach to the carrier segment such that the runners of the two blade track segments are adjacent to each other and define a bottom of the cavity formed by of the carrier segment.

In some embodiments, the flanges of the first retainer may include at least one aftwardly positioned flange for engagement with an aftwardly positioned hanger of the first blade track segment and at least one forwardly positioned flange for engagement with a forwardly positioned hanger of the first blade track segment. Each of the hangers may be formed to have an L-shape cross section including a radially extending portion and a forwardly extending portion.

In some embodiments, the carrier segment may include a carrier body, first and second circumferential endwalls, and first and second axial endwalls, and wherein each of the endwalls have an end seal recess disposed on a circumferentially outer side thereof. Each of the endwalls may extend radially inward from the carrier body. Each of the endwalls may have a radially inner end having a recess disposed therein sized to receive a compartment seal.

In some embodiments, the carrier segment may include a middle wall having a radially inner end that forms at least two recess disposed therein. Each recess of the middle wall may be sized to receive a compartment seal.

In some embodiments, the assembly may include a second blade track segment and a gap seal. The second blade track segment may include a runner that extends partway around the central axis and at least one hanger that extends radially outward from the runner. The gap seal may extend in the axial direction and may be arranged between the adjacent runners of the two blade track segments. The two blade track segments may cooperate to define recesses formed by features in a radially outer sides of the runners that receives the gap seal to provide sealing between the adjacent runners of the blade track segments.

According to another aspect of the present disclosure, a turbine shroud assembly that extends at least partway around a central axis is taught. The assembly may include a carrier segment comprising metallic materials and a first blade track segment comprising ceramic-matrix composite materials. The carrier may be formed to include a radially-inwardly opening cavity. The first blade track segment may be formed to include a runner that extends partway around the central axis and an attachment feature that extends outward in the radial direction from the runner into the radially-inwardly opening cavity of the carrier segment.

In some embodiments, the assembly may include a compartment seal. The compartment seal may extend around the attachment feature and may engage a radially-outward facing surface of the runner to seal at least a portion of the radially-inwardly opening cavity from gasses outside the radially-inwardly opening cavity.

In some embodiments, the compartment seal may be a one-piece component. The compartment seal may form an uninterrupted ring as it extends around the attachment feature. The compartment seal may be formed to include a plurality of radially-expandable folds configured to allow radial expansion and contraction of the compartment seal to accommodate thermal growth and contraction of the carrier segment and the first blade track segment.

In some embodiments, the carrier segment may include a carrier body, a first and second circumferential and walls that extend inward in the radial direction from circumferential ends of the carrier body, and first and second axial endwalls that extend inward in the radial direction from axial ends of the carrier body. Each of the first and second circumferential endwalls and the first and the second axial endwalls may be formed to include a radially-inwardly opening recess that each receive a portion of the compartment seal. In some embodiments, the radially-inwardly opening recesses cooperate to form an uninterrupted ring around the attachment feature.

In some embodiments, the assembly may include a second blade track segment. The second blade track segment may include a runner that extends partway around the central axis and an attachment feature that extends outward in the radial direction from the runner into the radially-inwardly opening cavity of the carrier segment. Chamfers along radially-outwardly facing circumferential ends of the runners included in the first blade track segment and the second blade track segment may cooperate to form radially-outwardly opening channel that receives a gap seal sized to seal a circumferential gap between the first blade track segment and the second blade track segment.

In some embodiments, the compartment seal may be a one-piece component extends around the attachment feature of the second blade track segment to form a ring around the attachment features of both the first blade track segment and the second blade track segment.

According to another aspect of the present disclosure, a method of assembling a segmented turbine shroud that extends around a central axis is taught. The method may include mounting a retainer formed to include flanges to a blade track segment formed to include a runner, hangers, and attachment posts so that the flanges engage the hangers and attaching the retainer to a carrier segment by coupling an attachment post of the retainer to the carrier segment so that the retainer and the hangers are received in a radially inwardly-opening cavity formed by a carrier segment.

In some embodiments, the method may include positioning at least one compartment seal in a recess of the carrier segment to engage a radially outer side of the runner of the blade track segment to seal the radially inwardly-opening cavity.

These and other features of the present disclosure will become more apparent from the following description of the illustrative embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

<figref idref="DRAWINGS">FIG. 1</figref> is a perspective view of a gas turbine assembly according to the present disclosure with a portion cut away to show that the assembly includes a compressor, a combustor, and a turbine with a segmented turbine shroud detailed in <figref idref="DRAWINGS">FIGS. 2 and 3</figref>;

<figref idref="DRAWINGS">FIG. 2</figref> is a cross-sectional view of a portion of the turbine shown in <figref idref="DRAWINGS">FIG. 1</figref> showing that the segmented turbine shroud includes a carrier segment that forms a radially inwardly-opening cavity, a retainer that attaches to the carrier segment and is arranged within the cavity, a blade track segment mounted onto the retainer to couple the blade track segment to the carrier segment, and a compartment seal that seals between the carrier segment and the blade track segment;

<figref idref="DRAWINGS">FIG. 3</figref> is a perspective view of a portion of an illustrative embodiment of the segmented turbine shroud segment of the turbine shroud of <figref idref="DRAWINGS">FIG. 2</figref> showing that the blade track segment mounts onto the retainer by engagement between hangers of the blade track and flanges of the retainer, and showing that the compartment seal is disposed around the hangers of each of the blade track segments and in contact with a top side of the blade track segment;

<figref idref="DRAWINGS">FIG. 4</figref> is a cross-sectional view of an illustrative embodiment of the segmented turbine shroud of <figref idref="DRAWINGS">FIGS. 2 and 3</figref> showing that the carrier segment is coupled to support multiple blade track segments that are each mounted onto retainers (shown in phantom), and showing that the retainers attach to the carrier segment by attachment posts that penetrate through openings in the carrier segment, and further showing that the carrier segment and one blade track segment are coupled together along with a compartment seal to form a sealed cavity within the carrier;

<figref idref="DRAWINGS">FIG. 5</figref> is an exploded perspective view the illustrative embodiment of the segmented turbine shroud of <figref idref="DRAWINGS">FIG. 4</figref> showing the details of the carrier segment, the retainers, and the blade tracks segments;

<figref idref="DRAWINGS">FIG. 6</figref> is a detailed cross-sectional view of the illustrative embodiment of the segmented turbine shroud of <figref idref="DRAWINGS">FIG. 4</figref> taken along the line <b>6</b>-<b>6</b> and showing that the compartment seal of the blade track segment is disposed within recesses of endwalls of the carrier segment and within a recess of a middle wall of the carrier segment and is disposed in contact with the top surface of the blade track segment to form a sealed compartment between the runner and the radially inwardly-opening cavity;

<figref idref="DRAWINGS">FIG. 7</figref> is a perspective view of a segmented portion of another illustrative embodiment of the turbine shroud of <figref idref="DRAWINGS">FIG. 2</figref> showing that the blade track includes a single compartment seal that is disposed about two adjacent blade track segments, and a strip seal positioned between the adjacent blade track segments and within a seal recess defined partly within the top surface and a circumferentially interior end side of each the adjacent blade track segments for discouraging combustion gases from flowing between the blade track segments; and

<figref idref="DRAWINGS">FIG. 8</figref> is a perspective view of a segmented portion of another illustrative embodiment of the turbine shroud of <figref idref="DRAWINGS">FIG. 7</figref> showing that the blade track includes a single compartment seal that is disposed about two adjacent blade track segments, and a rod seal that is positioned between the adjacent blade track segments that together define a seal recess formed by adjacent sloped interior circumferential end sides to receive the rod seal for discouraging combustion gases from flowing between the blade track segments.

DETAILED DESCRIPTION OF THE DRAWINGS

For the purposes of promoting an understanding of the principles of the disclosure, reference will now be made to a number of illustrative embodiments illustrated in the drawings and specific language will be used to describe the same.

An illustrative gas turbine engine <b>10</b> with a portion cut away is shown in <figref idref="DRAWINGS">FIG. 1</figref> to illustrate that the engine <b>10</b> includes a compressor <b>14</b>, a combustor <b>16</b>, and a turbine <b>18</b>. The compressor <b>14</b> compresses and delivers air to the combustor <b>16</b>. The combustor <b>16</b> mixes fuel with the compressed air from the compressor <b>14</b> and combusts the mixture. The hot, high-pressure exhaust products of the combustion reaction in the combustor <b>16</b> are directed into the turbine <b>18</b> to cause the turbine blade <b>20</b> to rotate about an axis <b>25</b> and drive the compressor <b>14</b>.

Referring now to <figref idref="DRAWINGS">FIG. 2</figref>, a portion of the turbine <b>18</b> is shown to include static turbine vane assembly <b>22</b> and a turbine wheel assembly <b>24</b>. The vane assembly <b>22</b> extends across the flow path of the hot, high-pressure exhaust gas from the combustor <b>16</b> to direct the exhaust toward blades <b>26</b> of the turbine wheel assembly <b>24</b>. The flow of combustion exhaust gas applies force to the blades <b>26</b> to cause the turbine wheel assembly <b>24</b> to rotate, thereby driving the rotating components of the compressor <b>14</b>. A segmented turbine shroud <b>28</b> extends circumferentially around axis <b>25</b> of the turbine wheel assembly <b>24</b> to encourage combustion exhaust to flow in a manner that applies force to the blades as suggested in <figref idref="DRAWINGS">FIG. 2</figref>.

Turbine shroud <b>28</b> illustratively includes a carrier <b>32</b>, a blade track <b>38</b>, and retainers <b>36</b> as shown in <figref idref="DRAWINGS">FIGS. 2-4</figref>. Carrier <b>32</b> illustratively supports blade track <b>38</b> through retainers <b>36</b> as suggested in <figref idref="DRAWINGS">FIGS. 2 and 4</figref>. Turbine shroud <b>28</b>, carrier <b>32</b>, and blade track <b>38</b> are each illustratively comprised of a respective plurality of turbine shroud segments <b>28</b><i>a</i>, carrier segments <b>32</b><i>a</i>, and blade track segments <b>38</b><i>a</i>. Each of turbine shroud segments <b>28</b><i>a</i>, carrier segments <b>32</b><i>a</i>, and turbine shroud segments <b>38</b><i>a </i>are arranged within a case <b>30</b> to form respective annular rings as suggested in <figref idref="DRAWINGS">FIGS. 1 and 2</figref>. In illustrative embodiments as shown in <figref idref="DRAWINGS">FIGS. 4 and 5</figref>, each turbine shroud segment <b>28</b><i>a </i>may comprise one carrier segment <b>32</b><i>a </i>attached to two retainers <b>36</b> and two blade track segments <b>38</b><i>a </i>each mounted to one of retainers <b>36</b>.

Carrier segment <b>32</b><i>a </i>comprises metallic materials and illustratively supports blade track segment <b>38</b><i>a </i>through retainers <b>36</b> as suggested in <figref idref="DRAWINGS">FIGS. 2 and 4</figref>. In the illustrative embodiment <b>4</b>, each blade track segment <b>38</b><i>a </i>of the blade track <b>38</b> mounts onto a retainer <b>36</b>, and retainers <b>36</b> illustratively attach to carrier segment <b>32</b><i>a </i>as shown in <figref idref="DRAWINGS">FIG. 3</figref>. The carrier segment <b>32</b><i>a </i>and each blade track segment <b>38</b><i>a </i>are illustratively arranged with a compartment seal <b>68</b> disposed to close a radially inwardly-opening cavity <b>70</b> of the carrier segment <b>32</b><i>a </i>to form a sealed compartment <b>72</b>. Carrier segment <b>32</b><i>a </i>illustratively attaches to case <b>30</b> to support blade track segment <b>38</b><i>a </i>for arrangement radially outward of blades <b>26</b> as suggested in <figref idref="DRAWINGS">FIG. 2</figref>.

Blade track segment <b>38</b><i>a </i>of blade track <b>38</b> includes a runner <b>40</b> and hangers <b>42</b> as suggested in the illustrative embodiment shown in <figref idref="DRAWINGS">FIG. 3</figref>. Blade track segment <b>38</b><i>a </i>is illustratively formed of ceramic matrix composite (CMC) material. In some embodiments, the CMC materials may include one or more of silicon carbide and oxides of aluminum. In some embodiments, blade track segment <b>38</b><i>a </i>may include any material suitable for gas turbine engine operation, such as aluminum alloy. Runner <b>40</b> includes a flow surface <b>45</b> on a radially inner side thereof for directing combustion exhaust flow towards the blades <b>26</b>, and an upper surface <b>47</b> that is configured to contact compartment seal <b>68</b> to form sealed compartment <b>72</b>. Blade track segment <b>38</b><i>a </i>includes hangers <b>42</b> extending radially outward from upper surface <b>47</b>.

Hangers <b>42</b> are configured to engage retainer <b>36</b> to mount blade track segment <b>38</b><i>a </i>to retainer <b>36</b> as suggested in <figref idref="DRAWINGS">FIG. 3</figref>. In illustrative embodiments, hangers <b>42</b> have an L-shape and extend radially outward from the runner <b>40</b> for a distance before extending for a distance in the forward direction of the gas turbine engine <b>10</b> as suggested in <figref idref="DRAWINGS">FIGS. 2-3</figref>. In some embodiments, hangers <b>42</b> may have any shape suitable for mounting blade track <b>38</b> to retainer <b>36</b>, such as extending for a distance in the circumferential direction of the gas turbine engine <b>10</b>. Hangers <b>42</b> engage with flanges <b>44</b> of retainer <b>36</b> to mount blade track segment <b>38</b><i>a </i>to retainer <b>36</b>.

Each retainer <b>36</b> includes a retainer body <b>46</b>, attachment posts <b>48</b>, and flanges <b>44</b> as suggested in <figref idref="DRAWINGS">FIGS. 2-4</figref>. Retainer body <b>46</b> is illustratively formed of a block <b>50</b> having an arm <b>52</b> attached to a forward side of block <b>50</b>. Arm <b>52</b> extends in the forward direction from the forward side of block <b>50</b> and includes a sloped top surface <b>53</b> that decreases in radial height progressively along at least a portion of its extension in the forward direction. Attachment posts <b>48</b> illustratively extend radially outward from the retainer body <b>46</b> for connection with the carrier segment <b>32</b><i>a. </i>

Attachment posts <b>48</b> of retainer <b>36</b> illustratively extend radially outward from block <b>50</b> of the retainer body <b>46</b> for connection with carrier segment <b>32</b><i>a </i>as illustratively suggested in <figref idref="DRAWINGS">FIGS. 2 and 3</figref>. In illustrative embodiments, attachment posts <b>48</b> are cylinders that extend along the radial direction of gas turbine engine <b>10</b>. In some embodiments, attachment posts <b>48</b> may have any shape suitable for connection with carrier body <b>34</b> to support blade track <b>38</b>. In illustrative embodiments, each attachment post <b>48</b> penetrates through an opening <b>54</b> of a carrier body <b>34</b> of carrier segment <b>32</b><i>a </i>to attach the retainer <b>36</b> to the carrier <b>32</b>.

Attachment posts <b>48</b> each illustratively have a top end <b>56</b> that extends above the carrier body <b>34</b>. Each top end <b>56</b> is illustratively configured for engagement with fasteners <b>60</b> to prevent removal of attachment posts <b>48</b> from their respective openings <b>54</b> as shown in <figref idref="DRAWINGS">FIGS. 4 and 5</figref>. Each fastener <b>60</b> is illustratively embodied as a bolt <b>61</b> having a spacer <b>63</b> sized to prevent removal of attachment posts <b>48</b> from openings <b>54</b> as suggested in <figref idref="DRAWINGS">FIGS. 4 and 5</figref>. In some embodiments, fasteners <b>60</b> may include any suitable type of fasteners such as shear pins that penetrate through the attachment posts perpendicular to the radial direction of gas turbine engine <b>10</b>. In some embodiments, attachment posts <b>48</b> may be attached to carrier segment <b>32</b><i>a </i>by any suitable manner including but not limited to bonding, welding, fastening, press fitting, etc.

Flanges <b>44</b> of each retainer <b>36</b> illustratively extend radially inward from retainer body <b>46</b> for engagement with blade track <b>38</b> as suggested in <figref idref="DRAWINGS">FIGS. 2-5</figref>. Flanges <b>44</b> are illustratively shaped complimentary to hangers <b>42</b> and extend radially inward for a distance before extending in the aftward direction of gas turbine engine <b>10</b> for a distance as suggested in <figref idref="DRAWINGS">FIGS. 2-3</figref>. In illustrative embodiments, each retainer <b>36</b> includes first, second, and third flanges <b>44</b><i>a</i>, <b>44</b><i>b</i>, <b>44</b><i>c </i>extending radially inward from the retainer body <b>46</b> to provide three points of contact with the blade track segment thereby locating the blade track segment in three dimensions, as suggested in <figref idref="DRAWINGS">FIG. 3</figref>.

First flange <b>44</b><i>a </i>is illustratively connected to arm <b>52</b> of retainer body <b>46</b> and is arranged to engage one of the hangers <b>42</b> of one blade track segment <b>38</b><i>a</i>. Second flange <b>44</b><i>b </i>and third flange <b>44</b><i>c </i>are illustratively connected to the block <b>50</b> of the retainer body <b>46</b> and are arranged to engage another of the hangers <b>42</b> of the same blade track segment <b>38</b><i>a</i>. Second and third flanges <b>44</b><i>b</i>, <b>44</b><i>c </i>are illustratively arranged in circumferentially spaced apart relation at opposite circumferential ends of block <b>50</b> as shown in <figref idref="DRAWINGS">FIGS. 3-5</figref>.

Carrier segment <b>32</b><i>a </i>includes carrier body <b>34</b>, middle wall <b>67</b>, and end walls <b>62</b>, <b>64</b> as illustrated in <figref idref="DRAWINGS">FIGS. 2 and 4-6</figref>. Carrier body <b>34</b> illustratively includes hangers <b>78</b> configured to engage the casing <b>30</b> to attach the carrier segment <b>32</b><i>a </i>to the casing <b>30</b>. Carrier body <b>34</b> illustratively includes a radially inner surface <b>76</b> that is sloped complimentary to the slope of top surface <b>53</b> of arm <b>52</b> of retainer <b>36</b> and is configured for contact therewith.

Middle wall <b>67</b> extends radially inward from the carrier body <b>34</b> to a middle wall end as shown in <figref idref="DRAWINGS">FIG. 6</figref>. Middle wall <b>67</b> illustratively includes two recesses <b>65</b> defined therein. Each recess <b>65</b> is configured to receive a portion of one compartment seal <b>68</b> for contact with an upper surface <b>47</b> of blade track segment <b>38</b><i>a </i>as shown in <figref idref="DRAWINGS">FIG. 6</figref>.

End walls <b>62</b>, <b>64</b> include circumferential end walls <b>62</b>, and axial end walls <b>64</b>. End walls <b>62</b>, <b>64</b> extend radially inward from the carrier body <b>34</b> to radially inward ends <b>62</b><i>e</i>, <b>64</b><i>e </i>thereof and define radially inwardly-opening cavity <b>70</b> as suggested in <figref idref="DRAWINGS">FIGS. 5 and 6</figref>. Radially inward ends <b>62</b><i>e</i>, <b>64</b><i>e </i>of the respective end walls <b>62</b>, <b>64</b> include recesses <b>66</b> defined therein and configured to receive compartment seal <b>68</b> for contact with an upper surface <b>47</b> of blade track segment <b>38</b><i>a</i>. Carrier segment <b>32</b><i>a </i>is illustratively coupled to blade track segment <b>38</b><i>a </i>with compartment seal <b>68</b> disposed in the recesses <b>66</b> of end walls <b>62</b>, <b>64</b> and in recess <b>65</b> of middle wall <b>67</b>, with the compartment seal <b>68</b> in contact with upper surface <b>47</b> of blade track segment <b>38</b><i>a </i>to close radially inwardly-opening cavity <b>70</b> and form sealed compartment <b>72</b>.

The compartment seal <b>68</b> illustratively seals off the compartment <b>72</b> from gasses outside the compartment <b>72</b> as suggested in <figref idref="DRAWINGS">FIGS. 2 and 3</figref>. The compartment seal <b>68</b> extends around the attachment features <b>42</b> of the blade track segment <b>38</b><i>a</i>. Illustratively, the compartment seal <b>68</b> is a one-piece metallic component that forms an uninterrupted ring around the attachment feature <b>42</b> as suggested in <figref idref="DRAWINGS">FIG. 3</figref>. The compartment seal <b>68</b> is formed to include radically-expandable folds <b>68</b><i>a</i>, <b>68</b><i>b</i>, <b>68</b><i>c </i>as shown in <figref idref="DRAWINGS">FIG. 3</figref>. The folds <b>68</b><i>a</i>, <b>68</b><i>b</i>, <b>68</b><i>c </i>allow radial expansion and contraction of the compartment seal <b>68</b> to accommodate thermal growth and contraction of the turbine shroud <b>28</b>.

Referring now to a second illustrative embodiment shown in <figref idref="DRAWINGS">FIG. 7</figref>, a segmented turbine shroud <b>128</b> includes a carrier segment <b>132</b><i>a</i>, blade track segments <b>138</b><i>a</i>, and retainers <b>136</b>. Segmented turbine shroud <b>128</b> is configured for use in engine <b>10</b> and is substantially similar to the turbine shroud <b>28</b> shown in <figref idref="DRAWINGS">FIGS. 1-6</figref> and described herein. Accordingly, similar reference numbers in the <b>100</b> series indicate features that are common between the turbine shroud <b>28</b> and turbine shroud <b>128</b> unless indicated otherwise. The description of segmented turbine shroud <b>28</b> is hereby incorporated by reference to apply to segmented turbine shroud <b>128</b> except in instances when it conflicts with the specific description and drawings of segmented turbine shroud <b>128</b>.

Unlike segmented turbine shroud <b>28</b>, segmented turbine shroud <b>128</b> includes a single compartment seal <b>168</b> arranged to encircle hangers <b>142</b> of both of the blade track segments <b>138</b><i>a</i>. Also, unlike segmented turbine shroud <b>28</b>, runners <b>140</b> of blade track segments <b>138</b><i>a </i>of segmented turbine shroud <b>128</b> define a seal recess <b>175</b> at a circumferentially interior end side <b>141</b> and a top surface <b>147</b> of the runners <b>140</b>. Each circumferentially interior end side <b>141</b> is positioned adjacent to and directly facing the circumferentially interior end side <b>141</b> of the other runner <b>140</b>. Seal recess <b>175</b> is at least partly defined within the top surface <b>147</b> and circumferentially interior side <b>141</b> of each runner <b>140</b> of the segmented turbine shroud <b>128</b>.

Seal recess <b>175</b> is configured to receive a gap seal <b>174</b> in sealing arrangement with the blade track segments <b>138</b><i>a </i>to discourage passage of exhaust gases between the runners <b>140</b>. Gap seal <b>174</b> is illustratively embodied as a strip seal having generally flat radially inner and outer surfaces as shown in <figref idref="DRAWINGS">FIG. 7</figref>. In some embodiments, gap seal <b>174</b> may contact the compartment seal <b>168</b> and or a middle wall <b>161</b> of the carrier segment <b>132</b><i>a</i>. The compartment seal <b>168</b> and the gap seal <b>174</b> are arranged with carrier segment <b>132</b><i>a </i>and blade track segments <b>138</b><i>a </i>to form a sealed compartment <b>172</b> and to encourage combustion exhaust to flow in a manner that applies force to the blades <b>26</b> of engine <b>10</b>.

In a third illustrative embodiment, a segmented turbine shroud <b>228</b> includes a carrier segment <b>232</b><i>a</i>, blade track segments <b>238</b><i>a</i>, and retainers <b>236</b>. Segmented turbine shrouds <b>228</b> is configured for use in engine <b>10</b> and is substantially similar to segmented turbine shrouds <b>28</b> and <b>128</b> shown in <figref idref="DRAWINGS">FIGS. 1-7</figref> and described herein. Accordingly, similar reference numbers in the <b>200</b> series indicate features that are common between segmented turbine shrouds <b>28</b>, <b>128</b> and the turbine shroud <b>228</b> unless indicated otherwise. The description of segmented turbine shrouds <b>28</b>, <b>128</b> is hereby incorporated by reference to apply to segmented turbine shrouds <b>228</b> except in instances when it conflicts with the specific description and drawings of segmented turbine shroud <b>228</b>.

Unlike the segmented turbine shroud <b>28</b>, but similar to segmented turbine shroud <b>128</b>, segmented turbine shroud <b>228</b> includes a single compartment seal <b>268</b> arranged to encircle hangers <b>242</b> of both of the blade track segments <b>238</b><i>a. </i>

Unlike both segmented turbine shrouds <b>28</b>, <b>128</b>, blade track segments <b>238</b><i>a </i>include runners <b>240</b> having sloped or chamfered circumferentially interior end sides <b>241</b> positioned adjacent to and partly facing the circumferentially interior end side <b>241</b> of the other runner <b>140</b>, but being sloped in the radially outward direction. Sloped interior end sides <b>241</b> together define a seal recess <b>275</b> configured to receive a gap seal <b>274</b>. Unlike the segmented turbine shroud <b>128</b>, circumferentially interior end sides <b>241</b> of runners <b>240</b> are slanted to face at least partially radially outward to form seal recess or channel <b>275</b>. Seal recess <b>275</b> is configured to receive a portion of rod seal <b>274</b> to prevent passage of exhaust gases between the runners <b>240</b> of the blade track segments <b>238</b><i>a. </i>

The compartment seal <b>268</b> and gap seal <b>274</b> are arranged with carrier segment <b>232</b><i>a </i>and blade track segments <b>238</b><i>a </i>to form a seal compartment <b>272</b> and to encourage combustion exhaust to flow in a manner that applies force to the blades <b>26</b> of engine <b>10</b>. Unlike segmented turbine shroud <b>128</b>, the gap seal <b>274</b> is illustratively embodied as a half rod seal having an arcuate shape on a radially inner side of its cross-section. In some embodiments, gap seal <b>228</b> may have any shape of cross-section suitable to discourage passage of exhaust gases between the runners <b>240</b>, for example a circular cross-section.

While the disclosure has been illustrated and described in detail in the foregoing drawings and description, the same is to be considered as exemplary and not restrictive in character, it being understood that only illustrative embodiments thereof have been shown and described and that all changes and modifications that come within the spirit of the disclosure are desired to be protected.